A group of 20 young people in Milwaukee learned recently what happens when water really gets polluted. They were part of an organization that is trying to clean up the Menomenee River, but when they waded into the water in search of debris, they began to experience a burning sensation on their legs. A spokesman for the restoration project said that soap and water would not remove the burning slime, and a doctor had to be called. He bathed them in a baking soda solution and the burning process was stopped. Afterwards, most of them looked as if they were suffering from severe sunburn. One restoration spokesman said: "We knew the river was polluted, but we didn't think water could ever get that bad."